Most of the herbs that are considered good for heart health in general, are also good for 'blood flow.'. Ahem...
Tinctures of Ashwaganda, Hawthorn Berry, Siberian Ginseng, Gingko Biloba, are where I would start. Also anything that 'makes heat' can be useful. Cayenne or Serrano Pepper tinctures, for example.
Endurance? Well, when you get that one, let me know.
One of the largest things I have noticed with men lacking in this area is not just stamina but their overall health. Many people I know (or have dated in the past) that party a great deal and consume unhealthy things end up being poor in the bedroom.
Good calls on both of you! Luckily for me, I haven't partied since, well, let's just say I'm past that. I'm lucky to have one or two beers when I'm out some where. Not a big drinker really, but I have noticed that definitely affected my performance.
Thanks for the tips folks. I used to take Ginko Biloba and that stuff would have me wired. I don't like energy drinks and only drink a little coffee in the mornings. Consuming Vitamin D3 has also really boosted my energy levels.